BEIRUT — Two suicide bombers blew up cars rigged with explosives near a military compound and a hotel in a city in northwestern Syria on Monday, killing at least eight people and tearing large craters in the ground, state media said.

The blasts were the latest setback for troubled U.N. efforts to end Syria’s 13-month-old crisis. A team of U.N. observers is already on the ground to salvage a cease-fire that went into effect April 12 but has been widely ignored by both sides. U.N. officials have singled out the regime as the main aggressor in violations of the truce.

There was no immediate claim of responsibility for Monday’s blasts in Idlib, a city in northwestern Syria. State media blamed “armed terrorists,” a term it uses for rebels trying to topple the government.

The state-run news agency SANA said among the eight dead were members of the security forces and civilians. The Britain-based Syrian Observatory for Human Rights, an activist network, said more than 20 people were killed in the explosions.

The bombers detonated their explosives near a military compound and near the city’s Carlton Hotel, SANA said.

A local activist, who only gave his first name, Ibrahim, for fear of repercussions, said the two sites are several hundred meters apart and that the explosions went off within five minutes of each other after daybreak Monday.

Two members of the U.N. observer team toured the site of the bombings, SANA said. Ibrahim said the observers have been staying at the Carlton, and a pro-government website reported that the hotel sustained some damage.

Syria’s pro-government al-Ekhbariya TV aired footage of the aftermath, showing torn flesh, smashed cars, twisted debris and blood stains on the pavement. The force of the explosions tore two large craters into the ground, shattered windows in the area and sent debris flying for hundreds of yards. Pro-government websites said dozens of people were wounded in the blasts and five buildings damaged.

Earlier Monday, gunmen fired rocket-propelled grenades at the central bank and a police patrol in the capital of Damascus, wounding four officers and causing light damage to the bank, SANA said.

Monday’s bombings were the latest in a series of suicide bombings to hit Syria.

An al-Qaida-inspired Islamist group called the Al-Nusra Front to Protect the Levant claimed responsibility Monday for a suicide bombing in downtown Damascus that killed at least 10 people Friday. The Associated Press could not verify the authenticity of Al-Nusra’s statement which was posted on a militant website.

On Sunday, the head of the U.N. observer team, Maj. Gen. Robert Mood, appealed to both sides to halt the fighting. “We want to have combined efforts focusing on the welfare of the Syrian people, true cessation of violence in all its forms,” he said after his arrival in the Syrian capital. Sixteen monitors are on the ground, but the team is to expand to 300.

Associated Press writer Albert Aji in Damascus contributed reporting.